论文部分内容阅读
一、甘薯在旱作农业中地位甘薯是耐早能力较强的块根作物。据初步观察:甘薯的根系发达,深达1.5米以下;而且块根内含有大量的水分,约占70%左右;甘薯没有明显的成熟期,所以对水分亏缺也没有特别敏感的时期。土壤水分不足时,如田间持水量降至40%左右(砂壤土含水率8～10%),茎叶生长和养分积累速度迟缓,但水分状况一旦改善,又可继续生长。在甘薯生长中、后期,即使在严重干旱条件下,土壤含水量降至田间持水量的20%(土壤含水率4～5%),植株仍然不致枯死,由此可见,甘薯的耐旱性比较强。近年来,在我省早薄地上甘薯种植面积仍然保持在1300万亩左右,春薯面积约600万亩,主要分布在
First, the status of sweet potato in dry farming Sweet potato is resistant to early strong root tuber crops. According to the preliminary observation, the root system of sweet potato is well developed, reaching a depth of 1.5m or less. Moreover, the tuberous root contains a large amount of water, accounting for about 70% of the total. The sweet potato has no obvious mature stage, so it is not particularly sensitive to water deficit. When the soil moisture is insufficient, if the water holding capacity in the field is reduced to about 40% (moisture content of sandy loam soil is 8-10%), the growth of stems and leaves and the accumulation of nutrients will be slow. However, once the water status is improved, the water can continue to grow. In the late and late stages of sweet potato growth, even in the severe drought conditions, the soil water content decreased to 20% of the field capacity (soil moisture content 4 ~ 5%), the plants are still not dead withered, we can see that the drought tolerance of sweet potato Strong. In recent years, the area of sweet potato planted in the precocious land of our province has remained at about 1,300,000 mu, with an area of about 6 million mu of spring potato, mainly distributed in the